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Dynamics of information diffusion and disease transmission in time-varying multiplex networks with asymmetric activity levels
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作者 谢笑笑 霍良安 +1 位作者 董雅芳 程英英 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期690-699,共10页
While the interaction between information and disease in static networks has been extensively investigated,many studies have ignored the characteristics of network evolution.In this study,we construct a new two-layer ... While the interaction between information and disease in static networks has been extensively investigated,many studies have ignored the characteristics of network evolution.In this study,we construct a new two-layer coupling model to explore the interactions between information and disease.The upper layer describes the diffusion of disease-related information,and the lower layer represents the disease transmission.We then use power-law distributions to examine the influence of asymmetric activity levels on dynamic propagation,revealing a mapping relationship characterizing the interconnected propagation of information and diseases among partial nodes within the network.Subsequently,we derive the disease outbreak threshold by using the microscopic Markov-chain approach(MMCA).Finally,we perform extensive Monte Carlo(MC)numerical simulations to verify the accuracy of our theoretical results.Our findings indicate that the activity levels of individuals in the disease transmission layer have a more significant influence on disease transmission compared with the individual activity levels in the information diffusion layer.Moreover,reducing the damping factor can delay disease outbreaks and suppress disease transmission,while improving individual quarantine measures can contribute positively to disease control.This study provides valuable insights into policymakers for developing outbreak prevention and control strategies. 展开更多
关键词 information diffusion disease transmission asymmetric activity levels quarantine strength
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Modified triphenylamine donors with shallower HOMO energy levels to construct long-wavelength TADF emitters of efficient organic light-emitting diodes
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作者 Hao Zhuo Ming Zhang +5 位作者 Hengyuan Zhang Hui Lin Gang Yang Silu Tao Caijun Zheng Xiaohong Zhang 《Chinese Chemical Letters》 2025年第5期330-335,共6页
Triphenylamine(TPA)is the most promising donor fragment for the construction of long-wavelength thermally activated delayed fluorescence(TADF)emitters owing to its suitable dihedral angle that could enhance radiative ... Triphenylamine(TPA)is the most promising donor fragment for the construction of long-wavelength thermally activated delayed fluorescence(TADF)emitters owing to its suitable dihedral angle that could enhance radiative decay to compete with the serious non-radiative decay.However,the moderate electron-donating capacity of TPA seriously limits the selection of acceptor for constructing longwavelength TADF emitters with narrow bandgaps.To address this issue,in this work,the peripheral benzene of TPA was replaced with 1,4-benzodioxane and anisole to obtain two new electrondonating units N-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-N-phenyl-2,3-dihydrobenzo[b][1,4]dioxin-6-amine(TPADBO,−5.02 eV)and 4-methoxy-N-(4-methoxyphenyl)-N-phenylaniline(TPAMO,−5.00 eV),which possess much shallower highest occupied molecule orbital(HOMO)energy levels than the prototype TPA(−5.33 eV).Based on TPA and the modified TPA donor fragments,three TADF emitters were designed and synthesized,namely Py-TPA,Py-TPADBO and Py-TPAMO,with the same acceptor fragment 12-(2,6-diisopropylphenyl)pyrido[2′,3′:5,6]pyrazino[2,3-f][1,10]phenanthroline(Py).Among them,Py-TPAMO exhibits the highest photoluminescence quantum yield of 78.4%and the smallest singlet-triplet energy gap,which is because the introduction of anisole does not cause significant molecule deformation for the excited Py-TPAMO.And Py-TPAMO-based OLEDs successfully realize a maximum external quantum efficiency of 25.5%with the emission peak at 605 nm.This work provides a series of candidate of donor fragments for the development of efficient long-wavelength TADF emitters. 展开更多
关键词 Organic light-emitting diodes Thermally activated delayed fluorescence Long-wavelength emission Triphenylamine Shallow HOMO energy level
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Measurement invariance and latent mean differences of the Chinese version physical activity self-efficacy scale across gender and education levels 被引量:3
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作者 Han Chen Jun Dai Yong Gao 《Journal of Sport and Health Science》 SCIE 2019年第1期46-54,共9页
Background: Self-efficacy has been identified as an important determinant of youth's behavior change including physical activity(PA) participation. However, the dimensionality check of a PA self-efficacy scale has... Background: Self-efficacy has been identified as an important determinant of youth's behavior change including physical activity(PA) participation. However, the dimensionality check of a PA self-efficacy scale has rarely been conducted in China. The current study aims to examine(1) the unidimensionality of a shortened Chinese version of PA self-efficacy scale(S-PASESC);(2) the measurement invariance of S-PASESC across gender and levels of education;(3) the latent factor mean difference between gender and levels of education;(4) the direct effects of self-efficacy on PA by different gender and education levels; and(5) the comparisons of the direct effects of self-efficacy on PA across gender and education levels.Methods: The participants were 5 th through 11 th grade public school students recruited from 7 cities located in different geographic regions of China. The final data include a total of 3003 participants(49.7% boys) who have completed the scales.Results: Confirmatory factor analysis(CFA) test supported the unidimensionality of S-PASESC. The S-PASESC is invariant across gender and 3 levels of education at both configural, full metric, and full scalar levels. Findings from latent mean comparisons showed that boys reported higher PA self-efficacy than girls. Students' perceived PA self-efficacy tend to decrease from elementary to high school. Finally, self-efficacy positively related to PA by groups of different gender and education levels and the relationship between self-efficacy and PA is stronger among middle school boys than girls.Conclusion: Findings suggest S-PASESC is a valid scale for measuring Chinese students' PA self-efficacy. 展开更多
关键词 Chinese adolescents Education levels Factor analysis GENDER LATENT mean comparison MEASUREMENT INVARIANCE Physical activity SELF-EFFICACY scale
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Diagnostic value of plasminogen activity level in acute mesenteric ischemia 被引量:3
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作者 Yusuf Gunerhan Neset Koksal +2 位作者 Munire Kayahan Yavuz Eryavuz Hilal Sekban 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第16期2540-2543,共4页
AIM: To investigate the changes in plasminogen activity level during mesenteric ischemia. METHODS: We performed laparotomy in 90 female Wistar-Albino rats (average weight 230 g). In sham groups (SL) (GroupsⅠand Ⅱ) t... AIM: To investigate the changes in plasminogen activity level during mesenteric ischemia. METHODS: We performed laparotomy in 90 female Wistar-Albino rats (average weight 230 g). In sham groups (SL) (GroupsⅠand Ⅱ) the superior mesenteric artery (SMA) and vein (SMV) were explored, but not tied. In SMA groups (Groups Ⅲ and Ⅳ) the SMA was ligated, and in SMV groups (Groups Ⅴ and Ⅵ) the SMV was ligated. On re-laparatomy 2 mL of blood was drawn at 1 h in groupsⅠ, Ⅲ and Ⅴ, and at 3 h in groups Ⅱ, Ⅳ and Ⅵ. Plasminogen levels were assessed and comparisons were made between groups and within each group. RESULTS: The mean plasminogen activity in the SL group was significantly higher than SMA (25.1 ± 10.8 vs 11.8 ± 4.6, P < 0.001) or SMV (25.1 ± 10.8 vs 13.7 ± 4.4, P < 0.001) groups both at 1 h and at 3 h (29.8 ± 8.9 vs 15.1 ± 5.7, P < 0.0001; 29.8 ± 8.9 vs 14.2 ± 2.9, P < 0.0001). There were no significant differences between the values of SMA and SMV groups at 1 h (P = 0.28) and at 3 h (P = 0.71). In each group, plasminogen activity levels did not change significantly between the two measurements performed at 1 h and 3 h. CONCLUSION: We conclude that blood plasminogen activities decrease during early phases of both arterial and venous mesenteric ischemia which may be a useful marker for early diagnosis. 展开更多
关键词 Mesenteric ischemia NECROSIS activity level
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A study of the relationship between expression level of TRF1 protein and telomerase activity in human acute leukemia 被引量:4
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作者 施继敏 黄河 +1 位作者 陈巧芳 林茂芳 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第2期154-158,共5页
Objective: To study the expression level of TRF1 (telomeric repeat binding factor 1) protein in human acute leukemia and relationship between expression level of TRF1 protein and telomerase, Methods: A quantitativ... Objective: To study the expression level of TRF1 (telomeric repeat binding factor 1) protein in human acute leukemia and relationship between expression level of TRF1 protein and telomerase, Methods: A quantitative Western±Blot technique was developed using anti±TRF1^33±277 monoclonal antibody and GST±TRFI purity protein as a standard to further determine the expression level of TRF1 protein in total proteins extracted from clinical specimens. Results: Bone marrow tissues of 20 acute leukemia patients were studied, 11 healthy donors' bone marrows were taken as a control. The expression level of TRF1 protein was significantly higher (P〈0.01) in normal bone marrow ((2.2174±0.462) μg/μl) than that of acute leukemia patients ((0.7544±0.343) μg/μl), But there was no remarkable difference between ALL and ANLL patients ((0.6184±0.285) μg/μl vs (0.8454±0.359) μg/μl, P〉0.05). After chemotherapy, TRFI expression level of patients with complete remission elevated ((0.7724±0.307)/μg/μl vs (1.6834±0,344)μg/μl, P〈0.01 ), but lower than that of normal ((2.2174±0.462)/μg/μl, P〈0.01). There was no significantly difference after chemotherapy ((0.7264±0.411) μg/μl vs (0.895±0.339) μg/μl,p〉0.05). TRF1 expression level of patients with complete remission is higher than that of patients without complete remission ((1,683±0.344)μg/μl vs (0.895±0.339)μg/μl P〈0.01). All samples were determined for telomerase activity. It was confirmed that the activity of telomerase in normal bone marrow was lower than that of acute leukemia patients ((0.125±0.078) μg/μl vs (0.765±0.284)μg/μl, P〈0.01). There was no significant difference of expression level ofTRF I protein between ALL and ANLL patients ((0.897±0.290) μg/μl vs (0.677±0.268) μg/μl, P〉0.05). After chemotherapy, telomerase activity of patients with complete remission decreased ((0.393±0.125) μg/μl), but was still higher than that of normal ((0.125±0.078) μg/μl, P〈0.01). Conclusion: The expression level of TRF1 protein has correlativity to the activity of telomerase (P〈0.001). 展开更多
关键词 Acute leukemia (AL) Human telomeric repeat binding factor protein 1 (TRFI) Monoclonal antibody Expression level of TRF1 protein Telomerase activity
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Evolution of the Level of Sunspot Activity in Solar Cycles I. Evolution in the Descending Phase 被引量:2
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作者 Jia-Long Wang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2006年第3期354-362,共9页
Taking the 13-point smoothed monthly sunspot number,Ri, and the deviation of the 13 associated monthly sunspot numbers from the smoothed one, Di, as a number-pair describing the global level of sunspot activity, the e... Taking the 13-point smoothed monthly sunspot number,Ri, and the deviation of the 13 associated monthly sunspot numbers from the smoothed one, Di, as a number-pair describing the global level of sunspot activity, the evolution of the level is statistically studied for the period from the month which is just 48 months before the minimum to the minimum in the descending phase, using the observed data of Solar Cycles 10 to 22. Our results show (1) for 46 months (94%) of the studied 49 months it is found that for a given month, the distribution of the 13 pairs which come from the 13 solar cycles on a log Ri - Di plane may be fitted by a straight line with a correlation coefficient larger than the critical one at confidence level a = 5%, and for 36 months (73%) the fitting is even better, for a = 1%; (2) time variations of these two parameters and their correlations in the studied period can be described respectively by functions of time, whose main trends may be expressed by a linear or simple curvilinear function; (3) the evolutionary path of the level of sunspot activity may be represented by a logarithmic function as log/~ = 0.704 lnDi - 0.291. 展开更多
关键词 Sun - sunspots - active level evolution
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Effects of Extracorporeal Shockwave Therapy and Hand Massage on Body Composition and Serum Lipids According to Serum Cholesterol Level in Korean Women 被引量:1
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作者 Kyung Jin Lee Jin Ik Park Soo Yeon Oh 《Journal of Cosmetics, Dermatological Sciences and Applications》 2019年第2期177-187,共11页
Obesity, particularly abdominal obesity, increases the risk of cardiovascular disease (CVD). This study investigates the effects of six-week (twice a week, 12 sessions total) extracorporeal shockwave therapy (SWT) and... Obesity, particularly abdominal obesity, increases the risk of cardiovascular disease (CVD). This study investigates the effects of six-week (twice a week, 12 sessions total) extracorporeal shockwave therapy (SWT) and hand massage therapy (HT) on body composition and serum lipids in overweight and obese Korean women aged between 35 and 59, according to their serum cholesterol level (≥200 mg/dL versus <200 mg/dL). After the program, weights decreased significantly in both the HT Group and SWT Group (p < 0.05);weights of those with cholesterol < 200 mg/dL significantly decreased in the HT Group (p = 0.038), while weights of those with cholesterol ≥ 200 mg/dL significantly decreased in the SWT Group (p = 0.001). BMIs decreased significantly in both the HT Group and the SWT Group (p < 0.05);BMIs of those with cholesterol < 200 mg/dL significantly decreased in the HT Group (p = 0.018), while BMIs of those with cholesterol ≥ 200 mg/dL significantly decreased in the SWT Group (p = 0.001). The body fat percentage of subjects significantly decreased only in the SWT Group (p = 0.027);the waist-hip ratio significantly decreased only in HT Group (p = 0.034). Serum cholesterol levels significantly decreased in those with cholesterol < 200 mg/dL in the HT Group (p < 0.05) and those with cholesterol ≥ 200 mg/dL in SWT Group (p = 0.055). Triglyceride significantly decreased in both those with cholesterol < 200 mg/dL and those with cholesterol ≥ 200 mg/dL, but did not significantly decrease in either subgroup of the HT Group. The study results suggest that SWT is effective in improving body measurements and serum lipids in those with cholesterol ≥ 200 mg/dL, while HT therapy is effective in those with cholesterol < 200 mg/dL. In conclusion, SWT and HT improved abdominal obesity by reducing body weight and waist circumference and helped improving serum lip index, suggesting the benefit for managing body measurements and serum lipids of overweight and obese individuals. 展开更多
关键词 SHOCKWAVE THERAPY hand MASSAGE Body Composition Cholesterol level
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Antiepileptic activity of lobeline isolated from the leaf of Lobelia nicotianaefolia and its effect on brain GABA level in mice
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作者 Abrar M Tamboli Rukhsana A Rub +1 位作者 Pinaki Ghosh SL Bodhankar 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第7期537-542,共6页
Objective:To investigate the anticonvulsant activity of the lobeline isolated from the Lobelia nicotianaefolia in chemoconvulsant-induced seizures and its biochemical mechanism by investigating relationship between se... Objective:To investigate the anticonvulsant activity of the lobeline isolated from the Lobelia nicotianaefolia in chemoconvulsant-induced seizures and its biochemical mechanism by investigating relationship between seizure activities and altered gamma amino butyric acid(GABA)in brain of mice in Pentylenetetrazol(PTZ) seizure models.Methods:The anticonvulsant activity of the isolated lobelinc(5,10,20 and 30 mg/kg.i.p.) was investigated in PTZ and strychnine induced seizures in mice and the effect of isolated lolieline on brain GABA level in seizures induced by PTZ.Diazepam was used as reference anticonvulsant drugs for comparison.Results:Isolated lobeliue(10,20 and 30 nig/kg.up.) significautly delayed and antagonized(P < 0.050-0.001)the onset of PTZ-induced seizures.It also antagonized strychnine induced seizures.The mortality was also prevented in the test group of animals.In biochemical evaluation,isolated lolieline(5,10and 20 mg/kg,i.p.) significantly increased the brain GABA level.And at dose of 30 mg/kg GABA level showed slight decrease in PTZ model.Conclusions:In our findings,isolated lolieline(20mg/kg) exhibited potent anticonvulsant activity against PTZ induced seizures.Also a biochemical evaluation suggested significant increase in harain GABA level at 20 nig/kg up.of isolated lolieline.Hence,we may propose that lolieline reduces epileptic seizures by enhancing the GABA release supporting the GABAergic mechanism. 展开更多
关键词 LOBELIA nicotianaefolia LOBELINE BRAIN GABA level ANTIEPILEPTIC activity Pentylenetetrazol(PTZ) STRYCHNINE
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Body Composition, Dietary Intake and Physical Activity Level of Sedentary Adult Indian Women
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作者 Gurpreet Kaur Kiran Bains Harpreet Kaur 《Food and Nutrition Sciences》 2012年第11期1577-1585,共9页
Age related changes in body composition are associated with long term dietary intake profiles. Age related increase in body fat is primarily attributed to decline in physical activity and basal metabolic rate as well ... Age related changes in body composition are associated with long term dietary intake profiles. Age related increase in body fat is primarily attributed to decline in physical activity and basal metabolic rate as well as dietary intake. The study was designed to assess the body composition, dietary intake and physical activity level of sedentary adult women of different age groups. A cross-sectional study was conducted on 152 sedentary adult women comprised of students and faculty from Punjab Agricultural University, Ludhiana. The relationship of body composition with dietary factors and physical activity level of women in four age groups i.e. 21 - 30, 31 - 40, 41 - 50 and 51 - 60 years was determined. A gradual increase (p ≤ 0.05) in anthropometric and body composition parameters such as weight, waist circumference, hip circumference, body mass index, fat mass and visceral fat rating was observed with the advancement of age. The lean body mass was decreased significantly (p ≤ 0.05) as the age progressed, the values for four age groups being 74.9, 68.9, 62.8 and 60.9%, respectively. Contrary to this fat mass increased with age, the corresponding values for four age groups being 15.7, 21.4, 26.6 and 29.2 kg, respectively. The percent adequacy of protein by four age groups was 69.6, 78.2, 80.0 and 66.3, respectively when compared to RDA while fat intake was much higher i.e. 245.5, 271.8, 288.4 and 250.8%, respectively. The energy intake was inadequate among all age groups, however, a significant (p ≤ 0.05) differ- ence was observed in daily energy consumption between the age groups. The mean physical activity level (PAL) of the subjects ranged between 1.49 - 1.60. The physical activity level values showed that majority of the subjects (87% - 94%) were having sedentary life style. Age is a crucial factor associated with body composition. A high fat mass and low lean body mass of the subjects was observed. Their diets were low in protein but high in fat. Majority of the subjects from different age groups had sedentary life style. A diet with higher protein and lesser fat combined with exercise can help in sustaining optimum body composition. 展开更多
关键词 LEAN Body MASS FAT MASS DIETARY Factors Physical activity level
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Effects of Physical Activity Levels on Fatigue Perception in Patients with Parkinson’s Disease and Neurologically Healthy Individuals
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作者 Paulo Cezar Rocha dos Santos Fabio Augusto Barbieri +2 位作者 Diego Orcioli-Silva Lucas Simieli Lilian Teresa Bucken Gobbi 《Health》 2014年第21期2927-2933,共7页
Background: Recent researches involving fatigue and Parkinson’s disease (PD) sought to verify its incidence and the impacts of fatigue on quality life of patients with PD. Despite the importance of regular physical a... Background: Recent researches involving fatigue and Parkinson’s disease (PD) sought to verify its incidence and the impacts of fatigue on quality life of patients with PD. Despite the importance of regular physical activity practice, there are only few studies that verified the influence of the levels of physical activity on fatigue in patients with PD. Objective: The aim of this study was to compare perception of fatigue between individuals with PD and neurologically healthy individuals (control group), considering the physical activity levels;and to verify the relation between physical activity levels and fatigue dimensions for individuals with PD and control group. Methods: Eighty individuals (40 patients with PD and 40 control individuals) participated in this study. Physical activity levels were evaluated through Modified Baecke Questionnaire for Older Adults. Multidimensional Fatigue Inventory (MFI) was used in order to evaluate fatigue dimensions (general, physical and mental fatigue, reduced motivation and activity). MANOVA two-way and Pearson linear correlation test were performed to analyze the data. Results: Patients with PD presented higher levels of fatigue, in all dimensions evaluated by MFI, comparing to control individuals. There was no association between physical activity levels and perception of fatigue for patients with PD and control individuals. Conclusion: Patients with PD showed increased perception of fatigue when compared to control individuals, due to PD characteristics. In addition, the perception of fatigue’s symptom was not influenced and had no relation by the level of physical activity. 展开更多
关键词 Parkinson’s Disease SYMPTOM of FATIGUE Physical activity levels NON-MOTOR SYMPTOM
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Physical Activity Level and Adult Saudi Health Related Quality of Life
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作者 Salwa B. El-Sobkey 《Open Journal of Therapy and Rehabilitation》 2014年第3期106-133,共28页
Purpose: Physical inactivity in Saudi Arabia is a growing challenge to public health. This study aimed to define the relationship between the physical activity level (PAL) and adult Saudi health-related quality of lif... Purpose: Physical inactivity in Saudi Arabia is a growing challenge to public health. This study aimed to define the relationship between the physical activity level (PAL) and adult Saudi health-related quality of life (HRQoL). Methods: Participants of this study were 100 Saudi adult aged from 18 - 70 years. The 36-Item Short-Form Health Status Survey (SF-36) was used to measure the participant’s HRQoL. The SF-36 is comprised of 8 domains. The electronic version of the General Practice Physical Activity Questionnaire was used to categorize participants in terms of physical activity level into;inactive, moderately inactive, moderately active, and active. Descriptive and inferential statistical tests were used to treat the collected data. Results: Results showed that only 17% of the Saudi adults had active PAL. The PAL had significantly positive relationship with 4 domains of HRQoL including: physical functioning (P = 0.004), role limitations caused by physical health problems (P = 0.048), vitality (P = 0.009), and general health (P = 0.044). Results also confirmed that the younger the subject, the higher the PAL (P = 0.0001) and the better the HRQoL. This is true for all domains except the role limitations caused by emotional problems and emotional wellbeing. Conclusion: The poor physical activity level of adult Saudi negatively impacts their HRQoL. 展开更多
关键词 SAUDI PHYSICAL activity level SAUDI Health Related Quality of Life SF-36 Survey General Practice PHYSICAL activity QUESTIONNAIRE
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What Is the Relation between Aerobic Capacity and Physical Activity Level in Adults with Congenital Heart Disease?
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作者 Kelly Ferri Maite Doñate +5 位作者 Mireia Parra Guillermo ROviedo Myriam Guerra-Balic Laia Rojano-Doñate Nicole Blackburn Ricard Serra-Grima 《Congenital Heart Disease》 SCIE 2021年第6期585-595,共11页
Background:Aerobic capacity(AC)in adults with congenital heart disease(CHD)is often reduced,mainly due to low confidence levels towards physical activity(PA).The main objective of this study was to estimate the associ... Background:Aerobic capacity(AC)in adults with congenital heart disease(CHD)is often reduced,mainly due to low confidence levels towards physical activity(PA).The main objective of this study was to estimate the association between PA level and AC(measured as peak of oxygen consumption,VO_(2peak))in adults with CHD.Methods:A total of 183 individuals(83 women and 100 men;mean(SD)age 36.9(11.0)years old)from Vall d’Hebron Hospital,Barcelona-Spain in 2019,participated in this cross-sectional study.The AC was assessed by cardiopulmonary exercise testing(CPET)using a treadmill ramp protocol.Considering values of metabolic equivalent of task(MET,MET-min·week-1)obtained by the short International Physical Activity Questionnaire(IPAQ),participants were divided into three categories of PA:health-enhancing PA(HEPA),minimally active,and inactive.Results:Median(SD)PA was 2737.2(2835.7)MET-min·week-1,with 60 participants(32.8%)reporting HEPA,91(49.7%)minimally active,and 32(17.5%)inactivity.Participants demonstrated a mean VO_(2peak) of 28.9(8.8)mL·Kg^(-1)·min^(-1),showing AC values on average 13%lower than expected in a healthy population.Overall,PA and AC were positively associated.Adjusting for sex and age,an increase of 1000 MET-min·week^(-1) was associated with an increase in VO_(2peak) of 0.8 units(95%CI 0.4–1.2;p<0.001).There were no differences in the degree of increase between sexes(p=0.427).Conclusion:These findings suggest that an increase in PA in patients with CHD significantly improves their AC,and hence,could be recommended when the goal is to improve their physical condition. 展开更多
关键词 Physical activity level aerobic capacity congenital heart disease
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Is HOMO Energy Level a Good Parameter to Characterize Antioxidant Activity 被引量:1
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作者 Hong Yu ZHANG De Zhan CHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第8期727-730,共4页
Semiempirical quantum chemical method AM1 was employed to calculate the highest occupied molecular orbital (HOMO) energy levels (E-HOMO) for various types of antioxidants. It was verified that the correlation between ... Semiempirical quantum chemical method AM1 was employed to calculate the highest occupied molecular orbital (HOMO) energy levels (E-HOMO) for various types of antioxidants. It was verified that the correlation between logarithm of free radical scavenging rate constants (1gks) and E-HOMO substantially arises from the correlation between E-HOMO and O-H bond dissociation energies (BDE) of antioxidants. Furthermore, E-HOMO were poorly correlated with the logarithm of relative free radical scavenging rate constants (1gk(3)/k(1)) for various types of antioxidants that possess complex structures (r = 0.5602). So in a broad sense, E-HOMO was not an appropriate parameter to characterize the free radical scavenging activity of antioxidants. 展开更多
关键词 AM1 ANTIOXIDANT free radical HOMO energy level O-H bond dissociation energy structure-activity relationship
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EFFECT OF MILD HYPOTHERMIA ON ACTIVITY NITRIC OXIDE SYNTHASE IN CORTICAL NEURONS AND GLYCEMIA LEVELS OF NEONATAL RATS WITH HYPOXIC ISCHEMIC BRAIN DAMAGE
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作者 Li Zhankui, Li Ruilin, Gou Yale et al (Department of Pediatrics, Second Affiliated Hospital, Xi′an Medical University) 《Journal of Pharmaceutical Analysis》 CAS 1999年第2期128-128,共1页
Through investigating the effect of mild hypothermia on activity of nitric oxide snythase (NOS) in cortical neurons and glycemia levels of neonatal rats with hypoxic ischemic brain damage (HIBD). We studied the mecha... Through investigating the effect of mild hypothermia on activity of nitric oxide snythase (NOS) in cortical neurons and glycemia levels of neonatal rats with hypoxic ischemic brain damage (HIBD). We studied the mechanism of protecting hypoxic ischemic neurons of mild hypothermia. We established neonatal rat HIBD models, used NOS immunohistochemistry and glycemia determination by micromethod. The number of cortical NOS positive neurons after hypoxic ischemia was significantly decreased as compared with controls. The glycemia levels was significantly increased than that controls. No significant difference was found in number of cortical NOS positive neurons and glycemia levels between 31℃ and 34℃ mild hypothemia. The results imply that hypothermia can decrease overproduction of NO through inhibiting the increase of the activity of NOS, and increase the glycemia levels, thus protect the hypoxic ischemic neurons. 展开更多
关键词 MILD RATS EFFECT OF MILD HYPOTHERMIA ON activity NITRIC GLYCEMIA levelS OF NEONATAL RATS WITH HYPOXIC ISCHEMIC BRAIN DAMAGE
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Terrestrial Temperature, Sea Levels and Ice Area Links with Solar Activity and Solar Orbital Motion
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作者 Valentina V. Zharkova Irina Vasilieva 《Natural Science》 2023年第9期233-255,共23页
This paper explores the links between terrestrial temperature, sea levels and ice areas in both hemispheres with solar activity indices expressed through averaged sunspot numbers together with the summary curve of eig... This paper explores the links between terrestrial temperature, sea levels and ice areas in both hemispheres with solar activity indices expressed through averaged sunspot numbers together with the summary curve of eigenvectors of the solar background magnetic field (SBMF) and with changes of Sun-Earth distances caused by solar inertial motion resulting from the gravitation of large planets in the solar system. Using the wavelet analysis of the GLB and HadCRUTS datasets two periods: 21.4 and 36 years in GLB, set and the period of about 19.6 years in the HadCRUTS are discovered. The 21.4-year period is associated with variations in solar activity defined by the summary curve of the largest eigenvectors of the SBMF. A dominant 21.4-year period is also reported in the variations of the sea level, which is linked with the period of 21.4 years detected in the GLB temperature and the summary curve of the SBMF variations. The wavelet analysis of ice and snow areas shows that in the Southern hemisphere, it does not show any links to solar activity periods while in the Northern hemisphere, the ice area reveals a period of 10.7 years equal to a usual solar activity cycle. The TSI in March-August of every year is found to grow with every year following closely the temperature curve, because the Sun moves closer to the Earth orbit owing to gravitation of large planets (solar inertial motion, SIM), while the variations of solar radiation during a whole year have more steady distribution without a sharp TSI increase during the last two centuries. The additional TSI contribution caused by SIM is likely to secure the additional energy input and exchange between the ocean and atmosphere. 展开更多
关键词 Sun: Magnetic Field Sun: Solar activity Sun: Inertial Motion Earth: Temperature Earth: Sea level Earth: Ice Area
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ENSO Index Variations and Links with Solar and Volcanic Activity
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作者 Valentina V. Zharkova Irina Vasilieva 《Natural Science》 2024年第4期25-44,共20页
In this paper, we investigated the Oceanic Niño Index (ONI), for simplicity called in this paper an El Nino Southern Oscillation (ENSO) index in 1950-2023 by applying the wavelet spectral transform and the IBM SP... In this paper, we investigated the Oceanic Niño Index (ONI), for simplicity called in this paper an El Nino Southern Oscillation (ENSO) index in 1950-2023 by applying the wavelet spectral transform and the IBM SPSS correlations analysis. ONI follows the three months’ current measurements of the average temperature of the sea surface in the East-Central tropical part of the Pacific Ocean nearby the international line of the date change over the average sea surface temperature over the past 30 years. The ENSO index is found to have a strong (>87%) correlation with the Global Land-Ocean Temperature (GLOT). The scatter plots of the ENSO-GLOT correlation with the linear and cubic fits have shown that the ENSO index is better fit by the cubic polynomial increasing proportionally to a cubic power of the GLOT variations. The wavelet analysis allowed us to detect the two key periods in the ENSO (ONI) index: 4 - 5 years and 12 years. The smaller period of 4.5 years can be linked to the motion of tectonic plates while the larger period of 12 years is shown to have a noticeable correlation of 25% with frequencies of the underwater (submarine) volcanic eruptions in the areas with ENSO occurrences. Not withholding any local terrestrial factors considered to contribute to the ENSO occurrences, we investigated the possibility of the volcanic eruptions causing ENSO to be also induced by the tidal forces of Jupiter and Sun showing the correlation of the underwater volcanic eruption frequency with the Jupiter-Earth distances to be 12% and with the Sun-Earth distances, induced by the solar inertial motion, in January, when the Earth is turned to the Sun with the southern hemisphere where the ENSO occurs, to become 15%. Hence, the underwater volcanic eruptions induced by tidal forces of Jupiter and Sun can be the essential additional factors imposing this 12 year period of the ENSO (ONI) index variations. 展开更多
关键词 Sun: Magnetic Field Sun: Solar activity Sun: Inertial Motion Earth: Temperature Earth: Sea level Earth: Ice Area
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中国积极老龄化事业发展水平的地区差异与收敛分析 被引量:3
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作者 李磊 黄志红 +1 位作者 王震 黄保聪 《经济地理》 北大核心 2025年第2期123-132,共10页
文章基于2006—2022年中国积极老龄化事业发展水平测度指标体系,采用Dagum基尼系数与方差分解法对中国及八大区域积极老龄化事业发展水平空间差异进行分解,并依托变异系数法和空间面板数据模型揭示其σ和β收敛特征。研究发现:(1)观察... 文章基于2006—2022年中国积极老龄化事业发展水平测度指标体系,采用Dagum基尼系数与方差分解法对中国及八大区域积极老龄化事业发展水平空间差异进行分解,并依托变异系数法和空间面板数据模型揭示其σ和β收敛特征。研究发现:(1)观察期内中国积极老龄化事业发展水平持续上升,但表现出明显的结构非稳定性与区域非均衡性特征。(2)区域间差异是地区总体差异的主要来源,结构差异的最大来源为友好环境维度的差异。(3)收敛检验结果显示,中国八大区域积极老龄化事业发展水平均具有σ收敛特性;除东北区域既不具备绝对β收敛也不具备条件β收敛,以及南部沿海区域不具备条件β收敛外,其他区域在考虑经济发展水平、人口年龄结构、政府政策导向、科学技术创新等影响因素后,积极老龄化事业发展水平差异将逐渐缩小,最终收敛至同一稳态水平。研究结论将为清晰认识中国积极老龄化事业发展格局提供事实依据,并对如何梯度推进积极应对人口老龄化国家战略,促进老龄事业均衡发展具有政策启示。 展开更多
关键词 积极老龄化 老龄事业发展水平 地区差异 结构差异 收敛分析
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基于浅层地震反射勘探技术的栟茶河断裂近地表构造特征研究 被引量:2
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作者 顾勤平 康清清 +13 位作者 杨浩 胡利 许汉刚 孟科 于俊杰 蒋新 赵启光 朱升初 薛莹莹 王金艳 李金良 张浩 徐烨 陈昊 《地球物理学报》 北大核心 2025年第3期938-955,共18页
早期对栟茶河断裂的研究成果局限在深部发育特征,至今仍未对该断裂的空间展布、最新活动时代及其与近地表地层的切割关系等重要科学问题开展过系统性的勘探和研究工作.鉴于此,本文按照“由已知到未知、由深到浅、分步探测、由点到线、... 早期对栟茶河断裂的研究成果局限在深部发育特征,至今仍未对该断裂的空间展布、最新活动时代及其与近地表地层的切割关系等重要科学问题开展过系统性的勘探和研究工作.鉴于此,本文按照“由已知到未知、由深到浅、分步探测、由点到线、由疏到密”的工作思路,采用不同工作方法和技术参数的浅层地震勘探对其进行了系统的探测和研究,并结合小间距钻孔联合地质剖面及新年代学样品测试等,查明了目标断裂近地表的空间分布位置和最新活动习性.研究结果表明:(1)栟茶河断裂是海安凹陷和通扬隆起的分界断裂暨控制苏北盆地沉积的断裂之一.(2)并非前人认识的一条断层,而是由2条N倾正断层组成的断阶带.中间走向近东西向,西段北西向,东段北东东向;视倾角约为60°~75°,是上陡下缓的铲形生长断层.(3)平面上呈向东(隆起区)收敛、向西(凹陷区)撒开趋势;向东发育并未延伸至原来认定的南黄海,而是终止于Ⅱ测线以西;向西延伸可能穿越了海安市主城区,继续追踪其空间位置的科学探索和系统研究工作显得非常重要且尤为必要.(4)小间距钻孔联合地质剖面成功定位了主断面在BCL1测线和BCL3测线分别位于7765和3660桩号处.难能可贵的是,在新庄村场地ZK2-5孔内中更新统启东组下段砂层中揭露了断层面,倾角约为70°.(5)确定了最新活动时代为中更新世晚期至晚更新世早期.(6)在栟茶河断裂南侧新发现了丁家所南缘断裂,它与栟茶河断裂夹持构成了鼻状地垒式的丁家所古潜山.(7)查明了栟茶河断裂的空间展布,已探明的长度为26 km.本文研究成果不仅为江苏地区相关城市的规划与建设、重大工程的建设选址及减轻地震灾害风险提供科学依据,填补了目标断裂所在测区近地表浅层地震探测研究和空间发育特征研究的空白,而且探测思路和研究方法对其他城市(尤其是厚覆盖区)活动断层探测和断裂活动性鉴定有借鉴和参考作用. 展开更多
关键词 栟茶河断裂 浅层地震勘探 多层次探测 钻孔联合地质剖面 活动断层
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新质生产力、技术交易市场活跃度与体育产业高质量发展--来自中国省级层面的经验证据 被引量:5
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作者 程名望 慈芳慧 王志远 《上海体育大学学报》 北大核心 2025年第1期65-75,共11页
基于2011—2022年中国28个省级行政区的面板数据,运用双向固定效应模型,实证分析新质生产力对体育产业高质量发展的影响及其作用机制。发现:①新质生产力对体育产业高质量发展具有显著的正向促进作用,这一结论在考虑内生变量和稳健性检... 基于2011—2022年中国28个省级行政区的面板数据,运用双向固定效应模型,实证分析新质生产力对体育产业高质量发展的影响及其作用机制。发现:①新质生产力对体育产业高质量发展具有显著的正向促进作用,这一结论在考虑内生变量和稳健性检验后依然成立;②在作用机制方面,培育和发展新质生产力可以有效提升技术交易市场活跃度,有助于体育领域科技成果转化,从而促进体育产业全要素生产率提升;③针对异质性分析,新质生产力在产业结构升级程度较低、经营环境较好的区域对体育产业高质量发展的推动效应更加显著。探讨新质生产力与体育产业的关系对于塑造体育产业发展新动能,促进体育产业高质量发展具有重要价值。 展开更多
关键词 新质生产力 体育产业 高质量发展 技术交易市场活跃度
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中老年人体力活动水平与认知功能的双向因果关系研究 被引量:1
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作者 李玉周 李禄一 王蕊 《体育学刊》 北大核心 2025年第4期137-143,共7页
中老年人体力活动与认知功能之间存在显著相关性,但潜在的因果关系仍需进一步厘清。研究利用2015年、2018年和2020年中国健康与养老追踪调查(CHARLS)的数据,使用固定效应和交叉滞后回归分析,对两者的因果关系进行量化考察。结果显示,控... 中老年人体力活动与认知功能之间存在显著相关性,但潜在的因果关系仍需进一步厘清。研究利用2015年、2018年和2020年中国健康与养老追踪调查(CHARLS)的数据,使用固定效应和交叉滞后回归分析,对两者的因果关系进行量化考察。结果显示,控制2015年(T1)和2018年(T2)时间点的认知功能后,T1时间点的高体力活动水平显著预测T2时间点的认知功能,T2时间点的高体力活动水平显著预测2020年(T3)时间点的认知功能。反之,在控制T1和T2的体力活动水平后,T1的认知功能显著预测T2的高体力活动水平,T2的认知功能显著预测T3的高体力活动水平。结果表明:中老年人高体力活动水平与认知功能之间存在显著的正相关关系和双向因果关系。早期高体力活动水平对后期的认知功能有显著预测作用,同时认知功能对后期的高体力活动水平也有显著影响。研究结果对制定有效的公共健康政策和个体健康促进具有重要意义。 展开更多
关键词 体力活动水平 认知功能 双向因果 中老年人
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